Stationary contact and terminal member



June 1, 1965 Original Filed Aug.

N. H. KOERTGE STATIONARY CONTACT AND TERMINAL MEMBER 2 Sheets-Sheet 1 a J -59 R u M 74 LVJ- Q L(:.'J 74 I III June 1, 1965 N. H. KOERTGE 3,187,149

STATIONARY CONTACT AND TERMINAL MEMBER Original Filed Aug. 31, 1960 2 Sheets-Sheet 2 United States Patent 3,187,149 STATIUNARY CGNTACT TERll/TENAL MEMBER This application is a division of the Nobel H. Koertge application Serial No. 53,200 filed August 31, 1960, now Patent No. 3,038,007, issued April 30, 1963, and is assigned to the assignee thereof.

This invention relates to an improved stationary contact and terminal member.

The primary object of the present invention is to provide a stationary contact and terminal arrangement affording re'ady convertibility from normally open to normally closed contact operation.

The foregoing object is accomplished by use of a U- shaped stationary terminal having a threaded hole in each leg of the U with such holes being aligned and providing a terminal screw having threads :adjacent its outer end only with the remainder of the shank of the screw being small enough to pass freely through the threaded holes. A relay or other housing on which the terminal is mounted is formed to receive the two legs of the contact so that a portion of the housing fits closely between such legs. When the threaded end of the screw has been turned through the threads in the hole in the top leg the screw drops down to the bottom leg and is screwed therein. The

head of the screw then captures a conductor against the top leg and compresses such leg against the housing portion between the legs of the U.

Other objects and advantages will be pointed out in, or be apparent from the specification and claims, as will obvious modifications of the embodiment shown in the drawings in which:

FIG. 1 is a front view of an electrical relay incorporating the invention;

FIG. 2 is an exploded view of the relay;

FIG. 3 is a partial sectional view taken on line 3-3 in FIG. 1 showing the movable and stationary terminals in norm-ally open position and;

FIG. 4 is a partial sectional View similar to FIG. 3 showing the movable and stationary terminals in normally closed position.

Referring to the drawings, a molded housing provides a mounting base for the other parts of the relay.

A contact carrier 40 is slidably guided inside the housing by ribs 42 and 44 on the carrier which mate with grooves 46 and 48, respectively, in the housing. These ribs are of a different size so that the carrier can only be assembled right side up in the housing. A notch 50 opens downwardly from the carrier and the top portion of lever 26 extends therein as well as the tongue of the spring plate. The sides of notch 50 are arcuate to accommodate movement of the armature lever and spring plate tongue when the carrier reciprocates. The carrier is biased toward the housing exterior by a coil spring 52 which seats in a depression in the housing at one end and around a boss 56 on the carrier at the other end. The carrier has a window 58 therein in which a movable contactor 59 is mounted by means of a spring 60 which fits around a pin 62 projecting into the window at one end and bears against contactor S9 at the other end. A pin 63 projects into the window from the other side to provide a mount for the spring when the terminal is reversed. The contactor has a central opening 64 through which such other pin projects when the termi- 1121 is in the position shown.

Another novel feature of this device is the way the stationary terminals 66 are reversibly mounted to cooperate with the reversible movable terminals to provide either normally open or normally closed switch operation. Each stationary terminal is U-shaped and has a silver contact plate 68 secured to'the inside of one leg. The housing is ape-rtured to accommodate and orient the legs of each stationary contact so that one leg is on either side of the movable contactor portions which extend laterally from the contact carrier. Each stationary terminal is held in place by .a screw which passes through the legs of the terminal and the housing. This screw has threads only adjacent its end and the remainder of its shank is of smaller diameter than the root diameter of the threads so that it is turned through the top leg and then drops down to the other leg into which it is then screwed. Thus it does not engage the top leg so that, when a wire is captured under the head of the screw, the screw head exerts a compressive force on the top terminal leg and forces it toward the bottom leg so that the legs tightly grip the housing portion therebetween. This drop through feature also reduces the time necessary to insert the terminal screw into operative position in the stationary terminal. The contact carrier 40 has a flange 70 on one end which catches on legs of the stationary terminals and serves to hold the carrier in the housing when the movable contactor 59 and stationary terminals 66 are in normally open position as shown in FIG. 3. When the movable contactor and stationary terminals are reversed as shown in FIG. 4, a normally closed con-tact relay is provided.

I claim:

1. A reversible electric stationary terminal comprising, a U-shaped member having a pair of spaced legs, said legs having alined threaded apertures and a binding screw having a threaded shank end portion'which screws into either of the leg apertures while the remainder of the shank can freely pass through said leg aperture whereby the screw can be taken down into the leg with which it is threadably engaged to compress said legs together and a contact tip secured to the inside of a leg of said member.

2. In an electrical device, a molded insulating base having a recess opening to one end, a notch opening to said one end and extending through one wall and a Window in said one wall in line with said notch, .a Ushaped terminal member having its parallel legs straddling the portion of said base between said notch and said window, said legs having alined threaded apertures which aline with an aperture in the straddle portion of said base and one leg thereof having a contact tip secured to the inside thereof within said recess, and a binding screw having a portion of its shank freely penetrating the aperture in the leg positioned within said notch and having the threaded end of its shank thre'adably engaging with the aperture in the other leg to compress the legs together and clamp the terminal in place against said straddled portion of the base.

3. The device in accordance with claim 2 wherein the diameter of the first mentioned portion of the screw shank V is such as to freely move through said apertures while that of the threaded end of the shank is such as to require screwing through either of the apertures in the terminal member legs and wherein the arrangement permits selec- .tive reversal of the mounted position of said terminal member on said straddled portion of said base about an axis parallel to its legs. 7

BERNARD A. GILHEANY, Primary Examiner.

Patented June 1, 1965 

1. A REVERSIBLE ELECTRIC STATIONARY TERMINAL COMPRISING, A U-SHAPED MEMBER HAVING A PAIR OF SPACED LEGS, SAID LEGS HAVING ALINED THREADED APERTURES AND A BINDING SCREW HAVING A THREADED SHANK END PORTION WHICH SCREWS INTO EITHER OF THE LEG APERTURES WHILE THE REMAINDER OF THE SHANK CAN FREELY PASS THROUGH SAID LEG APERTURE WHEREBY THE SCREW CAN BE TAKEN DOWN INTO THE LEG WITH WHICH IT IS THREADABLY ENGAGED TO COMPRESS SAID LEGS TOGETHER AND A CONTACT TIP SECURED TO THE INSIDE OF A LEG OF SAID MEMBER. 